Fuel feeder for furnace

Abstract

A chain-type fuel feeder which includes a chain conveyor that deposits coal onto a rotor which then throws the coal into a boiler-type furnace. The conveyor is driven from the shaft of the rotor by way of a novel, variable speed control assembly which includes separate, individual, totally integrated, commercially available drive units mounted on the sidewall of the feeder and exposed to ambient air so as to avoid overheating of the drive components and the problems associated therewith. The various drive components are arranged so that they are readily accessible for adjustment, repair, or replacement.

What is claimed is: 
     
       1. A feeder for feeding particulate fuel into a furnace comprising a housing having side walls, top and bottom walls, and a front wall having a discharge opening adapted to align with a charge opening in a wall of the furnace, said top wall having a fuel inlet opening for receiving fuel into said housing, rotor means adjacent said discharge opening including a rotor shaft with ends rotatably mounted on and extending beyond said side walls of said housing, fuel conveying means mounted in said housing to receive fuel from said inlet opening and to convey said fuel to said rotor means which then throws said fuel through said discharge opening into the furnace, power means connected to one end of said rotor shaft for rotating said rotor means, a variable speed drive assembly connecting the other end of said rotor shaft to said conveying means, said drive assembly including a self-contained adjustable speed drive unit having an input shaft, an output shaft, and adjusting means for regulating the speed of said output shaft, means mounting said adjustable speed unit from one wall of said housing, first drive means connecting the other end of said rotor shaft to said input shaft of said adjustable speed drive unit, a conveyor shaft rotatably mounted on said one wall of said housing and drive connected to said fuel conveying means, a self-contained speed reducer having an input shaft and a output shaft connected to said conveyor shaft, adjustable torque limiting means mounted on the input shaft of said speed reducer, and second drive means connecting said torque limiting means to said output shaft of said adjustable speed drive unit. 
     
     
       2. The feeder according to claim 1, wherein said adjustable speed drive unit and said speed reducer are exposed to ambient air. 
     
     
       3. The feeder according to claim 2, wherein said adjustable speed drive unit and said speed reducer are mounted in spaced relationship from one sidewall of said housing. 
     
     
       4. The feeder according to claim 3, wherein said torque limiting means and said first and second drive means are mounted axially outwardly of said adjustable speed drive unit and said speed reducer where they are readily accessible for adjustment, repair, or replacement. 
     
     
       5. The feeder according to claim 1, comprising alarm means responsive to an overload on said torque limiting means to indicate an abnormal condition of said fuel conveying means. 
     
     
       6. The feeder according to claim 1, wherein the output speed of said adjustable speed drive unit may be varied from 0 to some maximum RPM. 
     
     
       7. The feeder according to claim 1, wherein said speed reducer is a shaft-mounted type having a hollow output shaft mounted directly on said conveyor shaft. 
     
     
       8. A feeder for feeding particulate fuel into a furnace comprising a housing having sidewalls, top and bottom walls, and a front wall having a discharge opening adapted to align with a charge opening in a wall of the furnace, said top wall having a fuel inlet opening for receiving fuel into said housing, rotor means adjacent said discharge opening including a rotor shaft with ends rotatably mounted on and extending beyond said side walls, fuel conveying means mounted in said housing to receive fuel from said inlet opening and to convey said fuel to said rotor means which then throws said fuel through said discharge opening into the furnace, power means connected to one end of said rotor shaft for rotating said rotor means, a variable speed drive assembly connecting the other end of said rotor shaft to said conveying means, said drive assembly including a self-contained adjustable speed drive unit having an input shaft, an output shaft, and adjusting means for regulating the speed of said outlet shaft, means mounting said adjustable speed drive unit from one side wall of said housing, first drive means connecting said other end of said rotor shaft to said input shaft of said adjustable speed drive unit, said conveyor means including a rotatable shaft extending outwardly beyond said one sidewall of said housing, a self-contained shaft-mounted speed reducer having an input shaft and a hollow output shaft mounted on said conveyor shaft, adjustable torque limiting means mounted on said input shaft of said speed reducer, second drive means connecting said torque limiting mean to said output shaft of said adjustable speed unit, said adjustable speed unit and said speed reducer being mounted in spaced relationship from said one sidewall and being exposed to ambient air, and said torque limiting means and said first and second drive means being mounted axially outwardly of said adjustable speed drive unit and said speed reducer where they are readily accessible for adjustment, repair, or replacement. 
     
     
       9. A feeder according to claim 8 comprising alarm means responsive to an overload on said torque limiting means to indicate an abnormal condition of said fuel conveying means. 
     
     
       10. A feeder in accordance with claim 8 wherein said fuel conveying means is a continuous chain-type conveyor. 
     
     
       11. The feeder in accordance with claim 8 wherein the output speed of said adjustable speed drive unit may be varied from 0 to some maximum RPM. 
     
     
       12. A feeder for feeding particulate fuel into a furnace comprising a housing having side walls, top and bottom walls, and a front wall having a discharge opening adapted to align with a charge opening in a wall of the furnace, said top wall having a fuel inlet opening for receiving fuel into said housing, rotor means adjacent said discharge opening including a rotor shaft with ends rotatably mounted on said side walls of said housing, fuel conveying means mounted in said housing to receive fuel from said inlet opening and to convey said fuel to said rotor means which then throws said fuel through said discharge opening into the furnace, power means connected to said rotor shaft for rotating said rotor means, a variable speed drive assembly connected one end of said rotor shaft to said conveying means, said drive assembly including a self-contained adjustable speed drive unit having an input shaft, an output shaft, and adjusting means for regulating the speed of said output shaft, means mounting said adjustable speed unit from one wall of said housing, first drive means connecting said one end of said rotor shaft to said input shaft of said adjustable speed drive unit, a conveyor shaft rotatably mounted on said one wall of said housing and drive connected to said fuel conveying means, a self-contained speed reducer separate from said adjustable speed drive unit, said speed reducer having an input shaft and an output shaft connected to said conveyor shaft, adjustable torque limiting means mounted on the input shaft of said speed reducer, and second drive means connected said torque limiting means to said output shaft of said adjustable speed drive unit. 
     
     
       13. The feeder according to claim 12, wherein said adjustable speed drive unit and said speed reducer are mounted in spaced relationship from one sidewall of said housing. 
     
     
       14. The feeder according to claim 13, wherein said torque limiting means and said first and second drive means are mounted axially outwardly of said adjustable speed drive unit and said speed reducer where they are readily accessible for adjustment, repair, or replacement. 
     
     
       15. The feeder according to claim 12, wherein said speed reducer is a shaft-mounted type having a hollow output shaft mounted directly on said conveyor shaft.